*{margin: 0;padding: 0}
.nav{
    width: 990px;
    height: 460px;
    margin: 65px 179px 78px;
    overflow: hidden;
    position: relative;
}
.content img{
    width: 990px;
    height: 460px;
    position: absolute;  
}
.nav img:nth-of-type(1){
    z-index: 100;
}
button{
    cursor: pointer;
    width: 40px;
    height: 70px;
    background: url("../images/icon-slides.jpg");
    border: none;
    position: absolute;
    z-index: 200;
}
.position-center-y{
    position: absolute;
    top:50%;
    transform: translateY(-50%);
}
.prev{
    background-position-x: 83px;
}
.next{
    right: 0;
}
.next{
    background-position-x: 40px;
}
.prev:hover{
    background-position-x: 0;
}
.next:hover{
    background-position-x: -43px;
}
.foot{
    position: absolute;
    right: 35px;
    z-index: 300;  
    bottom: 22px;
}
.foot span{
    cursor: pointer;
    display: inline-block;
    width: 7px;
    height: 7px;
    border: 1.5px solid rgb(167, 168, 170);
    background-color: #848893;
    border-radius: 20px; 
}
.foot .active{
    background: #E7EBF8;
}